357 research outputs found
\u3ci\u3eThe Cyclops\u27s Neighbor\u3c/i\u3e
Hey, Polyphemus, what on earth\u27s the matter with you? roared Flagadonous, disturbed by howls coming from a nearby cave. Is someone trying to kill you
\u3ci\u3eThe Cyclops Maid\u3c/i\u3e
Being born on the right side of the right bed fulfilled all requirements for my family titles; honors so easily obtained are insignificant to me
Transurethral ultrasound diffraction tomography
ReportThe potential for cost-effective tomographic imaging using ultrasound continues to be confronted with difficulties arising from the computational complexity of fully three dimensional object reconstruction in the diffraction regime. Development of fast and accurate forward and inverse models for ultrasound propagation in the biomedical frequency range of 1-10 MHz is essential for diffraction tomography to be a practical imaging modality. We have implemented a flexible, object-oriented simulation system in MATLAB for performing rapid two- and three-dimensional modeling of forward scattering using the conjugate gradient FFT method in conjunction with a fast linear adjoint approximation to the Jacobian. Nonlinear conjugate gradient inversion has been implemented and tested in both 2D and 3D, demonstrating the feasibility of the method for diffraction tomography. We have also implemented and tested several regularization schemes including L2-norm and total variation, and have used multigrid iteration in conjunction with anisotropic diffusion filtering to accelerate convergence of the inversion algorithm. Inversions of strongly scattering objects have been successfully performed in 2D and 3D, and results thereof are presented herein
Angle-resolved photoemission study of untwinned PrBaCuO: undoped CuO plane and doped CuO chain
We have performed an angle-resolved photoemission study on untwinned
PrBaCuO, which has low resistivity but does not show
superconductivity. We have observed a dispersive feature with a band maximum
around (/2,/2), indicating that this band is derived from the undoped
CuO plane. We have observed another dispersive band exhibiting
one-dimensional character, which we attribute to signals from the doped CuO
chain. The overall band dispersion of the one-dimensional band agrees with the
prediction of model calculation with parameters relevant to cuprates
except that the intensity near the Fermi level is considerably suppressed in
the experiment.Comment: 6 pages, 10 figure
Investigation of Drying Curves of Lithium‐Ion Battery Electrodes with a New Gravimetrical Double Side Batch Dryer Concept Including Setup Characterization and Model Simulations
Herein, an experimental setup comprised of a stationary convection dryer (Comb Nozzle Dryer) supplemented by a measurement for gravimetric drying curves is introduced. The drying process of anodes for lithium‐ion batteries is experimentally investigated and compared to modeling results, showing very good agreement for the investigated films. Heat transfer coefficients of the issued impinging nozzles are characterized and measured quantitatively and are used for the drying simulation of the gravimetric drying experiments. In situ temperature changes in the films are measured and presented using an infrared camera setup
Interplane magnetic coupling effects in the multilattice compound Y_2Ba_4Cu_7O_{15}
We investigate the interplane magnetic coupling of the multilattice compound
Y_2Ba_4Cu_7O_{15} by means of a bilayer Hubbard model with inequivalent planes.
We evaluate the spin response, effective interaction and the intra- and
interplane spin-spin relaxation times within the fluctuation exchange
approximation. We show that strong in-plane antiferromagnetic fluctuations are
responsible for a magnetic coupling between the planes, which in turns leads to
a tendency of the fluctuation in the two planes to equalize.
This equalization effect grows whit increasing in-plane antiferromagnetic
fluctuations, i. e., with decreasing temperature and decreasing doping, while
it is completely absent when the in-layer correlation length becomes of the
order of one lattice spacing. Our results provide a good qualitative
description of NMR and NQR experiments in Y_2Ba_4Cu_7O_{15}.Comment: Final version, to appear. in Phys. Rev. B (Rapid Communications),
sched. Jan. 9
Influence of Layer Thickness on the Drying of Lithium‐Ion Battery Electrodes—Simulation and Experimental Validation
In this work, a detailed study of the drying of battery electrodes of different thicknesses is presented. A mathematical model to calculate the solvent loading and film temperature over the drying time is experimentally validated. The model is based on a first study presenting a simulation model to predict the drying course when linear drying kinetics prevail and no resistance exists for solvent transport within the film. To shed some light on the drying behavior of electrode films with different thicknesses, the start of capillary pore emptying is observed using a digital microscope. In the experiments, an onset of capillary transport even before the end of film shrinkage is observed for the electrode films with thicknesses above state-of-the-art-thickness. A clusterwise drying behavior becomes more distinct for thicker electrodes, with large areas of dry and wet capillaries next to each other, compared to a more homogenous drying of the thin electrodes. Based on these findings, the linear model is extended to consider transport limitations within the porous electrode film in the form of a moving drying front. The experiments show an increasing deviation from the linear model with increasing electrode thickness and the extended simulation, which considers transport resistances within the film, shows good agreement
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